Drying treatment method and apparatus

Abstract

A drying treatment apparatus for drying cleaned semiconductor wafers comprises drying gas producing means (41) connected to a drying treating unit (30) through a drying gas supplying pipe line (32). A flowrate controlling diaphragm pump (50) is provided in an isopropyl alcohol (IPA) supplying pipe line (32) that connects an IPA tank (48) and the drying gas producing means (41). An N2 gas supply source (52) is provided for supplying nitrogen gas into the drying gas producing means (41), and a heater (44) is disposed within the drying gas producing means to produce a drying gas. As a result of this, the amount of the IPA supplied to the drying gas producing means (41) by the diaphragm pump (50) is controllable, thus enabling the concentration of the IPA contained in the drying gas to be maintained at a value within a range of from 3% to 80%, inclusive, and enabling the temperature of the drying gas to be maintained at a value within a range of from 80 DEG to 150 DEG , inclusive, due to the heating by the heater (44). The above feature enables improvement of the drying efficiency and reduction in the amount of consumption of the drying gas.

What is claimed is: 
     
       1. A drying treatment method comprising the steps of: supplying a solvent at a controlled flowrate:   supplying an inert gas at a controlled flowrate:   mixing and heating said solvent and said inert gas to produce a drying gas having a solvent concentration in a range of three percent to eighty percent and having a temperature of 80 degrees Celsius to 150 degrees Celsius; and   supplying said drying gas into a drying treatment chamber and causing the drying gas to contact an object to be treated, said object contained in the drying treatment chamber, to dry the object.   
     
     
       2. The drying treatment method according to claim 1, further comprising the step of: reducing the pressure in said drying treatment chamber after said step of supplying said drying gas into the drying treatment chamber to dry the object.   
     
     
       3. A drying treatment apparatus comprising: drying treatment means having a drying treatment chamber containing an object to be treated;   a solvent supply source;   an inert gas supply source;   drying gas producing means including a mixing unit for mixing a solvent and an inert gas to obtain a mixed gas having a specific solvent concentration, and a heating unit for receiving and heating the mixed gas to produce a drying gas of a specific temperature;   a solvent supply pipe line connecting said solvent supply source to said mixing unit;   a flowrate-controllable solvent feed means provided in said solvent supply pipe line;   an inert gas supply pipe line connecting said inert gas supply source to said mixing unit;   a drying gas supply pipe line connecting said drying gas producing means to said drying treatment chamber to send the drying gas into the drying treatment chamber;   said solvent feed means being set to produce such a flowrate of the solvent which causes said solvent concentration in the drying gas to be maintained in a rage of three percent to eighty percent; and   said heating unit being set to maintain said specific temperature of the drying gas in a range of 80 degrees Celsius to 150 degrees Celsius.   
     
     
       4. The drying treatment apparatus according to claim 3, further comprising: a drying gas supply nozzle provided to said drying gas supply pipe line and disposed in said drying treatment chamber.   
     
     
       5. The drying treatment apparatus according to claim 4, wherein: said drying gas supply nozzle is movably provided relative to the object to be treated.   
     
     
       6. The drying treatment apparatus according to claim 3, further comprising: an exhaust pipe connected to said drying treatment chamber; and   an exhaust means provided in the exhaust pipe, to reduce a pressure of the drying treatment chamber.   
     
     
       7. The drying treatment apparatus according to claim 3, further comprising: heating means provided outside of the drying treatment chamber, for preventing condensation of the drying gas within the drying treatment chamber.   
     
     
       8. The drying treatment apparatus according to claim 3, further comprising: a discharge pipe connected to said drying treatment chamber; and   a gas/liquid separation unit provided to the discharge pipe, to separate the solvent in a used drying gas from the inert gas.   
     
     
       9. The drying treatment apparatus according to claim 8, wherein said gas/liquid separation unit comprises: a drying gas chamber for receiving a used drying gas;   cooling means for condensing the solvent contained in the drying gas;   a solvent discharge port provided at a bottom of said drying gas chamber to discharge the condensed solvent; and   an inert gas exhaust port provided at said drying gas chamber to discharge the separated inert gas.   
     
     
       10. The drying treatment apparatus according to claim 3, wherein: said solvent feed means comprises a diaphragm pump.   
     
     
       11. The drying treatment apparatus according to claim 3, wherein said mixing unit comprises: solvent vaporizing dishes disposed in multistages in vertical direction; and   means for supplying the solvent into the uppermost one of said dishes.